This is a matrix question but I can't get a single bracket so I will use two.

(a b)(5 1) =(12 -2)
(3 0)(-2 4) (15 3)

Find the values of a and b.

I can't make out where one matrix ends and the other starts

Do something like

1 2
3 4

x

4 3
6 7

=

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